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THE ORE DATABASE
Prospect 1833 - 110 Hesjelia
(Object Id: 2877)
(Last updated: 22.03.2024)
Belongs to the Province: Mofjellet sink-bly

Location
County: Nordland Municipality: Rana (1833)
Map 1:50000: Mo i Rana (1927-1) Map 1:250000: Mo i Rana
Coordinate system: EU89-UTM Zone 33
East: 460980 m. North: 7351434 m.
Longitude: 14.1307170 Latitude: 66.2803910
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Resource
Resource Type: Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) Resource Subtype: Zinc
Element(s): Zn Cu Kis
Importance
Raw material meaning: Not Assessed (reg. 09.02.2017)

Resources and production
Activity: Test mining Reserves: ,1 thousand tons
Operating method: Open pit mining Historical production: ,04 thousand tons


Products
Element/product Crude ore grade or quality Reg. date
Ag 11 ppm 22.03.2024
Cu .2 % 26.03.1992
Kis 20 % 26.03.1992
Pb 0.3 % 26.03.1992
Zn 3 % 26.03.1992

Operations
From - To Activity Comments
1959 - 1959 Core drilling
1976 - 1977 Geology
1977 - 1977 Geophysics
1984 - 1984 Core drilling
2007 - 2007 Geophysics Company/Institution :GEXCO Norge AS
TEM (by Skytem)
2008 - 2008 Core drilling Company/Institution :GEXCO Norge as
One drillhole between the Hesjelia and Hammertjønna deposits, which confirmed the connection between the two outcropping mineralizations.
2008 - 2009 Geology Company/Institution :NGU

Mineralization
Era: Proterozoic Period: Neoproterozoic
Genesis: Volcex Form: Ruler
Main texture: Durchbewegt Min. distribution: Semi-massive (20-50 % ore minerals)
Main grain size: Medium grained (1-3 mm) Main alteration:
Strike/Dip: 95 / 10 Direction: 95
Plunge: 5
Stratigraphic classification of host rock
Era: Proterozoic Period: Neoproterozoic
Province: Caledonides
Geotec.unit: Rødingsfjell Nappe Complex
Tectonic complex: Uppermost Allochthon
Igneous complex:
Group: Mofjell Group Formation:

Mineralogy
Relationship Mineral Amount
Gangue mineral Plagioclase Major mineral (>10%)
Gangue mineral Quartz Major mineral (>10%)
Gangue mineral Amphibole Subordinate mineral (1-10%)
Gangue mineral Biotite Subordinate mineral (1-10%)
Gangue mineral Epidote Subordinate mineral (1-10%)
Ore mineral Pyrite Major mineral (>10%)
Ore mineral Pyrrhotite Major mineral (>10%)
Ore mineral Sphalerite Subordinate mineral (1-10%)
Ore mineral Galena Accessory mineral (<1%)
Ore mineral Chalcopyrite Accessory mineral (<1%)

Lithology:
Relationship Rock Origin
Host rock Muskovittgneis Extrusive
Original rock :Tuff
Metamorphic facies :Amphibolite
Wall rock Granatglimmergneis Sedimentary
Original rock :Greywacke
Metamorphic facies :Amphibolite

Structures
Location: Type: Orientation(360 gr.): Relation to min.:
Host rock Foliation Strike/Dip :95 / 10 Post-mineralisation ;...Effect :None
Host rock Fold axis Strike/Dip :95 / 5 Post-mineralisation ;...Effect :Controls
Host rock Primary layering Strike/Dip :95 / 10 Syn-mineralisation ;...Effect :Controls

Information(s) in free text format
Free text
The Hesjelia zone is situated above a probable discordance on the top of Mofjellet. In this area two mineralizations (Hesjelia and Hammertjønna) are outcropping in a major fold closure of a recumbent fold structure oriented east-west. The structure has its closure to the south and has a length of c. 2.9 km. The mineralizations are associated with a tightly folded unit of muscovite gneiss. The outcrop of the mineralization at Hesjelia in the west has a length of about 130 m distributed on 5 prospects. The mapping during the NGU Mofjell project (2008-2013) and data from old drillholes show that the mineralization consists of several lenses and stripes of semimassive to massive sulfide mineralization in muscovite schist. From reports of the drilling in 1959 it is up to 4.9 m thick with 2.23 % Zn, and 0.16 % Cu. An average yields 2.9-3.4 % Zn and 0.2-0.25 Cu % at an average thickness of 2.95 m (Bjerkgård et al., 2009). Mapping by portable XRF showed the presence of a halo of barium and zinc above the mineralized zone. Geophysical data (TEM) indicated a connection between the mineralizations at Hammertjønna and Hesjelia and drillhole 4808 in 2008 strengthened this assumption. At about 110 m depth a weak mineralization was intersected in the hole assaying 0.14 % Cu, 0.09 % Pb, 0.60 % Zn and 3 g/t Ag over 6 m interval. Anomalous barium-values (up to 0.3 %) were found beneath the richest mineralization in the hole. Main sulfides in both Hesjelia and Hammertjønna are pyrrhotite or/and pyrite and sphalerite, while chalcopyrite is subordinate to accessory and galena is accessory mineral. The content of galena is generally slightly higher in the Hammertjønna deposits. Among trace minerals are silver-bearing phases, mainly freibergite, most common, but also some bismuth telluride are found. These phases are generally present as inclusions in galena. The mineralizations in the Hesjelia zone are characterized by high barium content, mainly present in hyalophane with 21-28% celsian component (analyses by SEM). In addition some barite was found in the Hesjelia showings, and barium-bearing mica with 2.5-5.5 wt. % Ba is present in both Hesjelia and Hammertjønna. The main gangue minerals in the Hesjelia zone are quartz, muscovite, biotite, plagioclase and hyalophane. Kyanite is quite common in the Hammertjønna deposits, while clinoamphibole (probably hornblende) is present in the Hesjelia deposits.

Bibliography:
From NGU's Reference Archive:
Bjerkgård, Terje ; Marker, Mogens ; Slagstad, Trond ; Solli, Arne , 2008
Mofjell-prosjektet. Statusrapport 2008
;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.2008.088;25 s. pages
Abstract:
Rapporten gir en status for Mofjellprosjektet, et 4-årig samarbeidsprosjekt mellom GEXCO Norge AS og NGU. Prosjektområdet er øst og sør for Mo i Rana, et område som kan inneholde økonomiske sulfidforekomster med Cu, Zn, Pb, Ag og Au. Målet er å få fram dette potensialet gjennom å kartlegge berggrunnen, de kjente og delvis drevne sulfidforekomstene og andre mineraliseringer i området. Berggrunnskartleggingen i 2008 har fokusert på den østlige delen av området, som omfatter fortsettelsen av Plurdalgruppen sørover og relasjonen til bergartsgrupper i øst. Dette innbefatter den viktige tidlig Kaledonske skyvestrukturen som kalles Langfjellsonen, som kan representere et malmgeologisk provinsielt skille, med jernmalmene i nord og sulfidforekomstene i sør. Under feltarbeidet ble det systematisk innsamlet 95 bergartsprøver til geokjemi, geokronologi og petrologi for å undersøke bergartenes dannelse som bakgrunn for relasjonen til malmgenese. Malmgeologiarbeidet har i 2008 fokusert på å skaffe oversikt over sulfidforekomster i Mofjellgruppen og en rekke nøkkelforekomster i de forskjellige mineraliserte sonene er kartlagt og prøvetatt. I tillegg har GEXCO innsamlet mange prøver, dels i form av håndstykkeprøver og dels i form av boring med packsack utstyr. Sammen med resultater fra GEXCOs diamantboringer viser arbeidet så langt at en rekke forekomster og soner i området kan være av økonomisk interesse og bør følges opp videre. De mest interessante områdene og forekomstene i Mofjellgruppen som peker seg ut så langt i tillegg til forekomstene i Mofjellet og Sølvberget er Hellerfjellet, Hesjelia-Hammertjønna, Heramb-Bertelberget og Småvatnan. Mer arbeid med dataene, blant annet sammenholdt med data fra tidligere prospekteringsaktivitet i området, er nødvendig for å komme nærmere inn på potensialet i både de ovenfor nevnte forekomstene og andre i området.

Bjerkgård, Terje ; Slagstad, Trond ; Solli, Arne ; Marker, Mogens , 2009
Mofjell-prosjektet: Statusrapport pr. juni 2009
;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.2009.038;31 s. pages
Abstract:
I alt ble 95 bergartsprøver innsamlet under feltarbeidet i 2008; av disse 81 prøver for geokjemi og 26 prøver for mineralseparasjon og aldersbestesmmelse (de fleste av disse også for geokjemi). Geokjemi av både amfibolitter og felsiske metavulkanitter i Mofjellgruppen viser øybuesignatur. Resultatene er således i stor grad i overensstemmelse med det som tidligere er publisert. En god del av de grå gneisene ser ut til å representere felsiske metavulkanitter, noe som betyr at det er et større innslag av vulkanske bergarter i området enn tidligere antatt. Dette kan også være en av grunnene til at området er anomalt når det gjelder gull-innhold. Det blir viktig å identifisere de tykkere enhetene med grå gneis. Dersom disse er vulkanske, kan de ha vært viktige som både varme- og metallkilde for dannelse av sulfidforekomstene.

Bjerkgård, Terje; Marker, Mogens; Slagstad, Trond; Solli, Arne , 2013
The Mofjell project: summary and conclusions
;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.2013.048;87 pages
Abstract:
The Mofjell project commenced in 2008 as a cooperation between GEXCO Norge AS, the county administration of Nordland and NGU. As GEXCO faced financial difficulties the external funding ended in 2009. The project area included Mofjellet and the eastern part of Plurdalen, an area with a large potential for economic sulfide deposits with Zn, Cu, Pb, Ag and Au. NGU has focused on establishing the geological setting of the Mofjell Group and its relation to ore formation. Another very important goal has been to assess the potential for economic ore deposits in the area, including enrichment of precious metals. On the basis of lithological observations and geochemistry, the Mofjell Group consists of a largely bimodal volcanic-sedimentary assemblage formed in an island-arc to back-arc setting. The data also show that the proportion of felsic volcanic rocks is much higher than previously described. A bimodal volcanic suite mixed with sediments is a geological environment which is regarded as favorable for both rich and large sulfide deposits.

References not to be found in NGU's Reference Archive.:
Sager, R. 1866: Erzgeologische Untersuchungen an Kaledonischen Blei, Zink und Kupfer fürenden Kieslagerstätten im Nord-Rana Distrikt, Nord-Norwegen. Doktoravhandling ETH, Zürich.


Kruse, A. 1980: Undersøkelse av Hesjelia. Internrapport nr. 8003. Bergverkselskapet Nord-Norge A/S.


Kruse, A. 1984: Hesjeli. Interimrapport. Status pr.10.09.1984. Intern rapp. nr. 8405, Prospektering A/S.

Fieldsamples
Sample No. Sample type Miscellanrous
HES-01-09 Bedrock
Sampler: T. Bjerkgård
Comment: Biotite-quartz gneiss with rich impregnation of sphalerite
No. of registrated element analyses = 1
HES-03 Bedrock
Sampler: T. Bjerkgård
Comment: Massive py-sl with minor cpy
No. of registrated element analyses = 1
HES-04 Dump
Sampler: T. Bjerkgård
Comment: Semimassive cpy-sl-py in quartz-sericite
No. of registrated element analyses = 1
NO0773.01 Bedrock
Sampler: Wilberg, R./...Stored: Løkken
Comment: Massiv sl-py-cpy-po-malm.
No. of registrated element analyses = 1
NO0773.02 Bedrock
Sampler: Wilberg, R./...Stored: Løkken
Comment: Massiv py-po-sl-malm.
No. of registrated element analyses = 1
NO0773.03 Bedrock
Sampler: Wilberg, R./...Stored: Løkken
Comment: Massiv py-po-sl-malm.
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:

Name of Locality: Skjerp 1
(Object Id: 3705 110,01,00)

Location
County: Nordland Municipality: Rana (1833)
Map 1:50000: Mo i Rana (1927-1) Map 1:250000: Mo i Rana
Coordinate system: EU89-UTM Zone 33
East: 460951 m. North: 7351392 m.
Longitude: 14.1300740 Latitude: 66.2800100
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Resource
Resource Type: Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) Resource Subtype: Zinc
Element(s): Zn Cu Kis
Resources and production
Activity: Pitting Reserves:
Operating method: Historical production:


Information(s) in free text format
Free text
Skjerp 1 ligger omlag 45 m SV for hovedskjerpet. Det er en ca. 3m lang skjæring som har avdekket malmsonen.Det er ca. 5 kbm tipp. Massiv finkornet pyritt-sinkblendemineralisering er avdekket.

Fieldsamples
Sample No. Sample type Miscellanrous
HES-02 Bedrock
Sampler: T. Bjerkgård
Comment: Semimassive sl-po-py with minor cpy in quartz-sericite
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:

Name of Locality: Skjerp 2
(Object Id: 3706 110,02,00)

Location
County: Nordland Municipality: Rana (1833)
Map 1:50000: Mo i Rana (1927-1) Map 1:250000: Mo i Rana
Coordinate system: EU89-UTM Zone 33
East: 461057 m. North: 7351355 m.
Longitude: 14.1324560 Latitude: 66.2796930
Show on map

Resource
Resource Type: Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) Resource Subtype: Zinc
Element(s): Zn Cu Kis
Resources and production
Activity: Pitting Reserves:
Operating method: Historical production:


Information(s) in free text format
Free text
Skjerp 2: 10 m lang røsk, omlag 1 m dyp. Lengst nordøst i røsken er det en ca. 20 cm massiv pyrittlinse. En tilsvarende linse med semimassiv pyritt finnes noen meter mot syd i røsken. Matriks er kvartsrik og er omgitt av kvarts-sericittskifer. Det er et lite skjerp ca. 10 m vest for røsken.

Fieldsamples
Sample No. Sample type Miscellanrous
HES-01 Dump
Sampler: T. Bjerkgård
Comment: Semimassive py-po with subordinate sl in quartz-sericite
No. of registrated element analyses = 1
NO0773.04 Bedrock
Sampler: Wilberg, R./...Stored: Løkken
Comment: Muskovittskifer med py og sl-disseminasjon.
No. of registrated element analyses = 1
NO0773.05 Bedrock
Sampler: Wilberg, R./...Stored: Løkken
Comment: Py-po-sl-malm.
No. of registrated element analyses = 1
NO0773.06 Bedrock
Sampler: Wilberg, R./...Stored: Løkken
Comment: Sukkerkornet kvarts med py-krystaller.
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:

Name of Locality: Skjerp 3
(Object Id: 36723 110,03,00)

Location
County: Nordland Municipality: Rana (1833)
Map 1:50000: Mo i Rana (1927-1) Map 1:250000: Mo i Rana
Coordinate system: EU89-UTM Zone 33
East: 461054 m. North: 7351480 m.
Longitude: 14.1323320 Latitude: 66.2808060
Show on map

Resource
Resource Type: Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) Resource Subtype: Zinc
Element(s): Zn Cu Kis
Resources and production
Activity: Pitting Reserves:
Operating method: Historical production:


Information(s) in free text format
Free text
Røsking/sprengt i kant av skrent. minst 3 m mektig sone med svak pyrittdisseminasjon med noe sinkblende.

Fieldsamples
Sample No. Sample type Miscellanrous
HES-02-09 Bedrock
Sampler: T. Bjerkgård
Comment: Quartz-sericite schist with scattered pyrite and sphalerite
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:


Analyse Results
from
Deposit Area 1833 - 110 Hesjelia

Element analyses

( *=parts pr. million, #=parts pr.billion, Negative values means below detection limit value.)
Sample No. Sample Type Cu* Zn* Pb* Co* Ni* Ag* Au#
HES-01 Dump 296 77 111 9 -5 2.0 30.0
HES-01-09 Bedrock 1990 32700 4500 2 12 19.0 70.0
HES-02 Bedrock 1660 107000 132 4 14 2.0 230.0
HES-02-09 Bedrock 1190 4020 101 -1 -5 9.0 70.0
HES-03 Bedrock 3980 94200 244 16 -5 4.0 50.0
HES-04 Dump 5160 78100 384 11 -5 6.0 150.0
NO0773.01 Bedrock 23910 62755 245 28 18 29.1 237.0
NO0773.02 Bedrock 16187 66926 204 28 22 16.9 54.0
NO0773.03 Bedrock 27866 82625 358 38 15 31.4 280.0
NO0773.04 Bedrock 2523 38447 482 5 7 4.5 16.0
NO0773.05 Bedrock 3696 5358 45 45 16 11.2 26.0
NO0773.06 Bedrock 50 501 2 8 4 1.0 16.0
------------------
Sample No. Pt# Pd# As* Cd* Ba* Mo* Sn* Sb* Bi*
HES-01 133 24.00 -1
HES-01-09 10 52500 33.00 2 20 27
HES-02 44248 14.00 3
HES-02-09 7 3470 2.00 2 15 6
HES-03 26513 11.00 1
HES-04 27856 10.00 3
NO0773.01 3.0 4.0 48 358.8 60 12.00 27 18
NO0773.02 4.0 4.0 76 366.7 52 4.00 28 21
NO0773.03 7.0 9.0 102 460.7 44 8.00 33 22
NO0773.04 1.0 5.0 15 213.2 23 7.00 3 6
NO0773.05 1.0 5.0 25 40.7 36 1.00 2 2
NO0773.06 1.0 3.0 14 11.9 2 7.00 2 2
------------------
Sample No. Ga* S% V* Cr* Mn* Fe% Th* U* W*
HES-01 2.00 232
HES-01-09 20.00 6.86
HES-02 17.00 697
HES-02-09 13.00 3.45
HES-03 9.00 465
HES-04 13.00 620
NO0773.01 25.24 5 1 748 28.20 3.00 5.00 1
NO0773.02 32.37 5 2 891 34.94 3.00 5.00 1
NO0773.03 32.27 6 2 860 29.68 3.00 7.00 1
NO0773.04 8.95 21 3 402 9.38 2.00 5.00 2
NO0773.05 33.50 2 1 749 37.68 1.00 5.00 1
NO0773.06 27.11 1 2 207 18.63 1.00 5.00 1
------------------
Sample No. Sr* La* B*
HES-01
HES-01-09
HES-02
HES-02-09
HES-03
HES-04
NO0773.01 8.0 4.00 30
NO0773.02 8.0 4.00 30
NO0773.03 8.0 4.00 37
NO0773.04 4.0 5.00 6
NO0773.05 2.0 2.00 2
NO0773.06 1.0 2.00 2


The fact sheet was created on 05.05.2024

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